1. Field of the Invention
The present invention relates to a collision prediction apparatus and method for predicting a collision between a vehicle such as an automobile and an object in front of the vehicle.
2. Description of the Related Art
As a protector for protecting a passenger when an automobile collides with an object in front, there exists the protector for fixing the passenger at his or her seat by: detecting the object in front with a radar mounted on the automobile; and in a case of determining that there exists a possibility of a collision, actuating a pretensioner mechanism of a seat belt, based on a distance and a relative speed till/with the object in front; and winding up the seat belt (for example, see paragraphs 0052 to 0060 and FIG. 1 in Japanese Patent No. 2946995).
In addition, there exists a protector for improving an impact absorption performance by: detecting a object in front with a radar mounted on an automobile; and in a case of determining that there exists a possibility of a collision, moving a front bumper forward; and providing a space between the front bumper and an automobile body frame before the collision (for example, see paragraphs 0013 and FIG. 1 in Japanese Patent Laid-Open Publication No. 2004-122908).
Because each protector described above actuates just before a collision, it is requested to accurately detect a distance from an automobile to an object and to predict the collision. Particularly, in a protector for moving a front bumper forward, because it is necessary to ensure a time for moving the front bumper forward just before a collision, it is necessary to accurately predict the collision.
However, because although a control unit of a conventional protector predicts a collision based on information in front of a vehicle obtained by using sensors such as a radar and a camera, a detection accuracy of the sensors varies according to a relationship between other vehicles and buildings and/or various environments such as a day, a night, and a bad weather, there is a problem that the collision cannot be always detected accurately.
Consequently, a collision prediction apparatus and method are strongly requested that solve the problem, can accurately detect an object in front of the vehicle according to variations of various traffic environments, and can accurately predict a collision.